BACKGROUND: Diphallus is an extremely rare anomaly. Numerous associated genitourinary, gastrointestinal and other anomalies have been described with diphallus. These patients need several investigations, and finally surgical intervention.CASES PRESENTATION: In this report we discuss six patients with diphallus which evaluated retrospectively. Five patients had complete diphallia, and one had bifid diphallus. Meatus was normal in 3, hypospadiac in 2, and epispadiac in one patient. The most common associated anomaly was bifid scrotum (5 cases), and other common anomalies consisted of bladder duplication (3 cases), imperforate anus (2 cases), and hypospadias (2 cases). Phalloplasty was performed for all but one.CONCLUSION: All the patients with urethral duplication have to be evaluated carefully because of the high incidence of other systemic anomalies.